Trianing?

I think my friend and I have officially decided to do the triathlon in August.  It is a small hometown one.  Nothing big.  But, it will be the perfect starting point for us.  So now I am trying to decided on a training program?  And yes!  I am that much of a sport or fitness nerd that I have looked up all sorts of them on line.

I function better when I have a plan.  I am not sure how I am going to do all the training.  With two kids in sports and a full time job.  I'm a bit overwhelmed just thinking about it.   So a plan is what I need.  It has been hard training for one sport at a time.  I am not sure how I will fit 3 in to a crazy schedule.  But, I will figure it out. 

Do you follow a written workout training program or do you wing it on your own??

My workouts for this week  look like this:
(So far)

Monday
Rest

Tuesday
Ran 3.5 miles at easy pace (morning)
Swim (Evening) 900 workout

Wednesday
Bike ride 30 minutes (morning)
Hopefully an evening run
Track workout 6x200s

Thursday
Run 3.5 or maybe some intervals
Swim (Evening) 1000 workout

Friday
Rest
(Bethany's Birthday Party!)

Saturday
Swim (?)
Run a nice easy run.  :

Sunday
Bike ride 30 minutes

I'm looking for ideas for taking my running to the next level.  I can run miles at an average pace.  I want to be able to at least do a 5k at a faster pace.  Any suggestion on how to do this with only running 2 to 3 times a week?

Happy Tuesday